1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
anyanavicka [17]
2 years ago
12

Solve for x. Determinants

Mathematics
1 answer:
joja [24]2 years ago
6 0

Remember that row operations don't affect the determinant:

\begin{vmatrix}x+a&x&x\\x&x+a&x\\x&x&x+a\end{vmatrix}=\begin{vmatrix}a&a&0\\0&a&a\\-a&0&a\end{vmatrix}

(that is, subtract row 2 from row 1; subtract row 3 from row 2; and subtract row 1 from row 3. This is not the only way to do it, of course.)

Factoring out a gives

a^3\begin{vmatrix}1&1&0\\0&1&1\\-1&0&1\end{vmatrix}

Notice that adding rows 1 and 3 gives the same numbers in row 2. In other words, the rows are not linearly independent, which means the matrix is singular, and this is so for any value of x.

You might be interested in
Which set is closed under subtractionWhich answer choice shows that the set of irrational numbers is not closed under addition
vovikov84 [41]

Answer:

(a) Set of rational numbers

(b) \pi + (-\pi) = 0

Step-by-step explanation:

Solving (a): Set that is closed under subtraction

The solution to this is rational numbers.

For a set of number to be closed under subtraction, the following condition must be true

a -b = c

Where

a, b, c are of the same set.

The above is only true for rational numbers.

e.g.

1 - 2 = -1

5 - 5 = 0

\frac{1}{2} - \frac{1}{4} = \frac{1}{2}

4 - 2 = 2

The operations and the result in the above samples are rational numbers.

Solving (b): Choice not close under addition[See attachment for options]

As stated in (a)

For a set of number to be closed under subtraction, the following condition must be true

a -b = c

Where

a, b, c are of the same set.

In the given options (a) to (d), only

\pi + (-\pi) = 0 is not close under addition because:

\pi is irrational while 0 is rational

<em>In other words, they belong to different set</em>

8 0
2 years ago
a mail truck picks up two boxes of mail from the post office. the total weight of the boxes is 32 pounds . one box is 8 pounds h
Dmitrij [34]
One box is 24lb another box is 8 because i half of 32 is 16 and 1/2 of 166 is 8 so 16 + 8 = 24 leaving another 8 behind

4 0
3 years ago
Solve 5-3^x=-40 round to the nearest ten-thousandth
solong [7]

5-3^x = -40

 subtract 5 from each side to get

-3^x=-45

 divide both sides by -1 to make them positive

3^x = 45

need to do the natural logarithm on both sides to remove the variable from the exponent

 so ln(3^x) = ln(45)

 use logarithm rule to move x out

x ln (3) = ln(45)

 dive each term by ln(3) then simplify to get

ln(3)/ln(45)

 so x = ln(3)/ln(45) which calculates out to 3.46497352

round off to ten thousandths is 3.4650

 

4 0
3 years ago
Read 2 more answers
What is the value of x?<br><br> A. 2_/3<br> B. 4_/4<br> C. 4<br> D. 6
Xelga [282]

The answer is b this is because you add the angles


8 0
3 years ago
a light bulb consumes 5280 watt hours in 5 days and 12 hours. how many watts hours does it consume per day?
sammy [17]

Answer:

For this we first need to know how much watt hours are used in 12 house which we can find by taking 960/2=480 now we just need to take 960*4=3840 and add 480 which gives us are end answer of 4320 watt hours.

Step-by-step explanation:

7 0
3 years ago
Read 2 more answers
Other questions:
  • How do you get the slope-intercept form for -2x+3y=15? Please show steps and explain
    8·1 answer
  • Marina paid $2,000 for a tablet PC after receiving a 25 percent discount. What was the price of the tablet before the discount?
    10·1 answer
  • What value do the roman numerals CIX represent?
    8·1 answer
  • The table of values below represents a linear function and shows the weight of a kitten as it has grown. What is the output for
    14·1 answer
  • A survey of 1,000 people was done by New York Times. 80% of the people did not know the name of their representative in Congress
    8·1 answer
  • If f and g are two functions defined by f(x)=3x+5 and g(x)=x^2+1 find f^-1 (x)
    7·1 answer
  • Suppose there is a 1.1 drop in temperature for every thousand feet that an airplane climbs into the sky. If the temperature on t
    10·1 answer
  • Use the Distributive Property to rewrite the algebraic expression. 5(2x + 7)
    13·1 answer
  • Complete the equations so that the solution of the system of equations is (-3, 5)​
    14·1 answer
  • Ask...<br> Find the length of HK<br> HELPPPPP
    15·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!